KR100433747B1 - Methods of inhibiting plant damage by nematodes - Google Patents

Abstract

A method for suppressing plant damage by nematodes which comprises the concurrent administration, to the locus, soil or seeds of plants in need of such treatment, of (a) a metabolite of the fungus Myrothecium verrucaria and (b) a chemical pesticide, as well as synergistic nematocidal compositions useful therein.

Description

Methods of inhibiting plant damage by nematodes

Nematodes, including plant propagation nematodes, such as Meloidogyne , Heterodera , Pratylenchus and Xiphinema , are grown annually on crops, vegetables, fruits, flowering trees and shrubs It costs millions of dollars. Nearly all major plant species can be infected with these pests, which not only can affect the roots of host plants, but can also damage parts of the ground including stems, leaves and flowers. As a result, there is a great need to control these parasites, and in the past, these controls have been used for chemical pesticides such as 1,3-dichloropropene, 2,3-dihydro-2,2-dimethyl-7-benzofuranylmethyl (1-methylethyl) phosphoramidate and methyl N, N'-dimethyl-N - [(methylcarbamoyl) oxy] -1- Date). ≪ / RTI > These compounds can be very effective, but many have been found to be harmful to the environment and in some cases the usage / frequency of use of these compounds has been limited by the regulatory authorities, resulting in the weakening of the effects of these nematicides.

As a result, efforts have been made to find effective means of inhibiting nematode damage while avoiding or reducing the use of chemical insecticides. One solution is to use a biochemical nematicide having a specific mode of action and a relatively safer toxicological profile instead of a chemical insecticide. Examples of such alternative nematicides include ABG-9008 (a metabolite of Myrothecium verrucaria fungi described and claimed in U.S. Patent No. 5,051,255, issued September 24, 1991) (Or related compounds such as milbemycin) and fatty acids (described and claimed in U.S. Patent No. 5,346,698, issued September 13, 1994). Another solution is the spore and organophosphate nematicide of the nematode bacterial parasitic Pasteuria penetrans (described in Australian Patent 60573/86, published Jan. 29, 1987) . However, the industrial scale production of Pasteuria penetrans spores is difficult due to the fact that the organism is an absolute protozoan, so it must be propagated only in the nematode and separated from the necrotically infected root degradation product. Therefore, when using chemical insecticides, there is a need for improved nematode control measures that significantly reduce the use of chemical insecticides.

SUMMARY OF THE INVENTION

In accordance with the present invention, when one or more metabolites produced by the fermentation of Myrothecium verrucaria are combined with chemical insecticides, the use of chemical insecticides alone or in combination with a much lower amount of insecticides than required It was found that effective inhibition of nematodes was possible. Surprisingly, the compounding effect is merely synergistic rather than additive in that nematode control is possible by using a lower application rate than is normally required for the activity of both metabolites and pesticides.

Therefore, in one embodiment of the present invention, it is characterized by simultaneous administration of the fungus Myrothecium verrucaria metabolite (a) and the chemical insecticide (b) to the plantation, soil or seed of the plant for which treatment is required , Thereby suppressing plant damage caused by nematodes. These two agents are considered to be " co-administered " when applied simultaneously (the formulation is administered in the form of a combined composition) or separately (but both agents are present in the same co-existing and active manner in the same plant or soil) .

The metabolites used herein may be in the form of whole culture medium (including mycelium) obtained by culturing fungi of Myrothecium verrucaria species. Alternatively, the metabolites may be one or more specific fractions or components separated, extracted and purified from the medium according to methods well known in the art. Further, when the structural formula of the component is known, it is expected that it can be synthesized de nove by a known chemical method. As used herein, " metabolite " means any of the above; However, the metabolites of the present invention are preferably whole-culture preparations obtained by fermentation and heat-sterilization of Myrothecium verrucaria , in particular Myrothecium verrucaria strain ATCC 46474.

The broad carnivorous activity of chemical insecticides can be enhanced by co-administration with the above metabolites. However, organophosphates and carbamate insecticides are preferred among the insecticides of the present invention. Representative chemical insecticides useful in the claimed process include methyl propiolate, phenamphos and oxamyl.

In each of the above cases, the method of the present invention can be carried out by administration of an insecticide with an insufficient amount of metabolites to effectively control the nematode when administered alone. &Quot; Effective control " means reducing the damage to the plant so that the nematode treatment is cost effective and sufficient to avoid significant economic losses without further nematode suppression. Specifically, the recommended rate when using chemical insecticides alone for the control of nematodes [the "label rate" listed on the product package and approved by the appropriate government agency] is 50% or less . Particularly, it is preferable that the insecticide and the metabolite are administered at a ratio of not more than 50% and not more than 75% of the respective display ratios when these agents are used singly.

In another preferred embodiment of the method, the chemical insecticide is administered at a rate of about 1% to about 30% of the recommended rate when used alone in the control of the nematode. When the insecticide (about 1% to about 30% of the labeling ratio) is used as a metabolite alone, a method that is applied together with a metabolite to be administered in a ratio of about 50% of the labeling ratio is particularly preferable, Is considered to be the best method considered.

In another embodiment of the present invention, the carnivorous composition is described as comprising a chemical insecticide together with a metabolite of the fungus Myrothecium verrucaria . One such specific composition is that the fungus is Myrothecium verrucaria strain ATCC 46474. Among these compositions, it is preferred that the insecticide is an organophosphate insecticide or carbamate insecticide, and more particularly preferred compositions include those wherein the insecticide is selected from methyl propiolate, phenamphos and oxamyl.

The present invention relates to a carnivorous composition useful for controlling agricultural pests. In particular, the present invention relates to a synergistic combination of a biopesticide and a chemical insecticide obtained from Myrothecium verrucaria fungus, which is used at a significantly lower rate than when a chemical insecticide is used alone . The present invention also relates to the use of said composition and / or the simultaneous administration of said pesticide with a chemical insecticide to effectively inhibit nematode damage.

Metabolites of Myrothecium verrucaria suitable for use in the methods and compositions of the present invention are those obtained by fermentation of myrothecium verrucaria strain ATCC 46474; Such a metabolite is commercially available as the bionematocidal product ABG-9008 from Abbott Laboratories, North Chicago, Ill. The preparation of such metabolites is also described in detail in U.S. Patent No. 5,051,225, which is incorporated herein by reference.

Representative organophosphate chemical insecticides useful in the present invention are ethyl 3-methyl-4- (methylthio) phenyl (1 (methylthio) phenyl) phenol sold commercially as Penamifos or product NEMACUR 3 from Miles, Inc. of Kansas City, -Methylethyl) -phosphoramidate < / RTI >; Other organophosphates include ethoprofos, diclofenitone, diamidaphos, pheysulfothion, postethiene, diazopos and thiazines. Representative carbamate chemical insecticides useful in the present invention include methyl N, N ' -dimethyl-pyrrolidone commercially available as PRATT OXAMYL 10% G from Oxamil or Miller Chemical & Fertilizer Corp., Hanover, Pa. N - [(methylcarbamoyl) oxy] -1-thioxamidimidate.

When applied separately, the metabolites and insecticides of the present invention may be administered according to their respective product handling instructions. When applied as a composition of the present invention, the metabolites and insecticides may be mixed in any suitable form (e.g., a solvent, suspension, emulsion, powder or mixture of granules) and applied manually or by spraying, , To a drench, or to a newly planted plant or other mounted means. Such compositions further comprise a surfactant polysorbate 80 in the case of solvents, surfactants, emulsifiers, swelling and flow enhancers and / or other excipients such as aqueous emulsions or solvents known in the field of agricultural insecticides and fertilizer formulations .

Optimal rates of application of the metabolites and pesticides for the control of specific target nematodes and conditions can be readily measured without undue experimentation by simple distribution studies conducted in a greenhouse or outdoor set. Based on the results, it is expected that considerable nematode control could be achieved by using 50% of the recommended ratio of metabolites and 10% to 25% of the recommended rate of insecticide. The methods and compositions include, but are not limited to, Meloidogyne species such as Meloidogyne incognita , Meloidogynearenaria , Meloidogyne javanica , And Meloidogyne chitwoodi ; Anguina species, such as the eye or Anguina tritici ; Ditylenchus species, such as Ditylenchus destructor and Ditylenchus dipsaci ; Pratylenchus species, such as Pratylenchus penetrans ; Heterodera species such as Heterodera glycines and Heterodera schachtii ; Aphelenchus species, for example Aphelenchus avenae ; Radopholus species, for example Randopholus similis ; Xiphinema species such as the Xiphinema index ; It is expected to add to the ethylene kusu (Rotylenchus) species, such as ethylene kusu Lenny formate miss would be effective against a wide range of nematodes, including (Rotylenchus reniformis).

The methods and compositions of the present invention are better understood with regard to the following examples and are intended to illustrate the invention and not to limit the scope of the invention. Throughout the following and throughout the specification, citations to the literature are specifically incorporated by reference.

Example 1

Greenhouse evaluation of methyl propiolate and ABG-9008

The effect of Myrothecium verrucaria metabolites ABG-9008 and methyl propiolate (Aldrich Chemical Co., Wisconsin) on root infections by Meloidogyne incognita The cucumber seedlings are grown in duplicate per pot, at each port of 2 inches (5 cm) in diameter, containing approximately 125 g of a sterile mixture of sand and soil (2: 1). The plants are grown in a greenhouse maintained at 28 DEG C and water is given constantly on a daily basis. On the day of initiation, the plants were treated with nematode 15 ml drenches in an aqueous solution of 0.1% polysorbate 80 (or solution vehicle alone), and then 800 Meloidogyne incognita candles Inoculate the jovenile. On the sixth day, the plants are harvested, the roots washed, and the number of root hump is counted under a dissecting microscope. The results of each treatment or control (in each case n = 8 plants) are shown in the following Table 1, where the reduction rate of root hump formation is expressed as a percentage of the number of humps observed in untreated control plants.

These results clearly demonstrate the synergistic effect of the chemical insecticide ABG-9008, a metabolite of Myrothecium verrucaria . For example, the amount of methylpropiolate alone (0.75 mg per pot) capable of 5% reduction of root hump formation alone, in an amount capable of 27% reduction of root hump formation (0.5 g per pot ) Of ABG-9008 is sufficient to reduce the root hump formation by 61%.

Example 2

Greenhouse assessment of Penamifos and ABG-9008

The effect of ABG-9008 and organophosphate phenaminosis on root infestation by Meloidogyne incognita is tested as follows: Cucumber seedlings are grown in a 5 inch diameter 12.7 cm), three pieces per port are grown in the same manner as described above except that they are grown. The plants are treated with 120 ng drenches of the nematicide treatment or control solution on the day of initiation and then 1200 Meloidogyne incognita super bodies are inoculated into each pot. On day 14, the plants are harvested, the roots are washed, and the number of root horns is counted under a dissecting microscope. The results of each treatment or control (in each case n = 12 plants) are shown in Table 2 below.

The Penamifos product used is NEMACUR 3 (Miles Inc., Kansas City, Missouri), and its recommended display ratio is 5.3 pounds per acre (1.6 μm per port, based on surface area). The above results demonstrate synergism between the metabolites of the present invention and the chemical insecticide, whereby phenanthrene used in a ratio of 1/4 of the recommended ratio (a rate that does not give any effect to the nematode) Can be reduced by up to 82% when administered simultaneously with ABG-9008 at a rate that can only reduce by 54%.

Example 3

Greenhouse assessment of Penamifos and ABG-9008

Experiments in Example 1 and Example 2 are repeated using cucumber seedlings planted at two ports per port, at each port of 2 inches (5 cm) in diameter, containing about 125 g of a sand / soil mixture. The plants are treated on day one with a nematicide treatment agent or a control group of 15 ml drenches and then 800 Meloidogyne incognita superfamilies are inoculated into each pot. On the fifth day, the plants are harvested, the roots are washed, and the number of root hump is counted under a dissecting microscope. The results of each treatment agent or control (in each case n = 6 plants) are shown in Table 3 below.

The Penamifos product used is NEMACUR 3 (Miles Inc., Kanas City, Missouri), and its recommended labeling rate is 2.5 liters per acre (0.4 μl per pot, based on surface area). The results again demonstrate the synergy between the metabolites of the invention and the chemical pesticide.

Example 4

Greenhouse assessment of Oxamil and ABG-9008

The effect of ABG-9008 and carbamate insecticide oxymyl on root infestation by Meloidogyne incognita is tested as follows: Cucumber seedlings are grown in 2 inch diameter (5 cm diameter) containing about 125 grams of sand / ) Are grown in the same manner as described above, except that they are grown two at each port. The plants are treated with 15 ng drenches of the nematocide treatment or control (s) on the initiation day and then 800 Meloidogyne incognita super bodies are inoculated in each pot. On the fifth day, the plants are harvested, the roots are washed, and the number of root hump is counted under a dissecting microscope. The results of each treatment or control group (in each case n = 6 plants) are shown in Table 4 below.

The oxamil product used is PRATT OXAMYL 10% G (Miller Chemical & Fertilizer Corp., Hanover, Pa.) And the recommended amount is 35 kg per acre (13 mg per port based on surface area). The product is completely dissolved in water before being treated with the plant. The results again demonstrate the synergy between the metabolites of the invention and the chemical pesticide.

It is to be understood that the foregoing detailed description and accompanying examples are for the purpose of illustration only and are not intended to limit the scope of the present invention, and that the scope of the present invention is limited only by the appended claims and equivalents thereof. Various changes and modifications to the specific embodiments described will be apparent to those skilled in the art. Without deviating from the spirit and scope of the present invention, the present invention is not limited to the active agents and excipients of the present invention, and the above changes and modifications are possible including them.

Claims (8)

(A) obtained by fermenting and heat-sterilizing the fungus Myrothecium verrucaria strain ATCC 46474 on the locus, soil or seed of a plant which is required to be inhibited by the nematode, A method for inhibiting plant damage by nematocides, comprising the step of simultaneously administering a chemical insecticide (b) selected from the group consisting of a naphosphate insecticide, a carbamate insecticide and methyl propiolate. 2. The method of claim 1, wherein the insecticide is phenamphos. The method of claim 1, wherein the insecticide is oxamyl. The method according to any one of claims 1, 2 and 3, wherein the whole-culture preparation obtained by fermentation and heat-sterilization of Myrothecium verrucaria strain ATCC 46474 and the insecticide are used alone In an amount less than an effective amount for controlling the nematode when administered. The method according to any one of claims 1, 2, and 3, wherein the insecticide is administered at a rate of 50% or less of the display ratio when the insecticide is used alone in the nematode control. 6. The method according to claim 5, wherein the whole-culture preparation obtained by fermenting and heat-sterilizing the fungus Myrothecium verrucaria strain ATCC 46474 is used in an amount of not more than 75% Lt; / RTI > The method according to any one of claims 1, 2, and 3, wherein the insecticide is administered at a rate of about 1% to about 30% of the indication rate when the insecticide is used alone in the nematode control. 8. The method according to claim 7, wherein the whole-culture preparation obtained by fermentation and heat-sterilization of Myrothecium verrucaria strain ATCC 46474 is used in an amount of about 50% Lt; / RTI >